#include <srs_kernel_mp3.hpp>

#if !defined(SRS_EXPORT_LIBRTMP)

#ifndef _WIN32
#include <unistd.h>
#endif

#include <fcntl.h>
#include <sstream>
using namespace std;

#include <srs_kernel_log.hpp>
#include <srs_kernel_error.hpp>
#include <srs_kernel_stream.hpp>
#include <srs_kernel_file.hpp>
#include <srs_kernel_codec.hpp>

SrsMp3Encoder::SrsMp3Encoder() {
    writer = NULL;
    tag_stream = new SrsStream();
}

SrsMp3Encoder::~SrsMp3Encoder() {
    srs_freep(tag_stream);
}

int SrsMp3Encoder::initialize(SrsFileWriter* fw) {
    int ret = ERROR_SUCCESS;

    srs_assert(fw);

    if (!fw->is_open()) {
        ret = ERROR_KERNEL_MP3_STREAM_CLOSED;
        srs_warn("stream is not open for encoder. ret=%d", ret);
        return ret;
    }

    writer = fw;

    return ret;
}

int SrsMp3Encoder::write_header() {
    char id3[] = {
        (char)0x49, (char)0x44, (char)0x33, // ID3
        (char)0x03, (char)0x00, // version
        (char)0x00, // flags
        (char)0x00, (char)0x00, (char)0x00, (char)0x0a, // size

        (char)0x00, (char)0x00, (char)0x00, (char)0x00, // FrameID
        (char)0x00, (char)0x00, (char)0x00, (char)0x00, // FrameSize
        (char)0x00, (char)0x00 // Flags
    };
    return writer->write(id3, sizeof(id3), NULL);
}

int SrsMp3Encoder::write_audio(int64_t timestamp, char* data, int size) {
    int ret = ERROR_SUCCESS;

    srs_assert(data);

    timestamp &= 0x7fffffff;

    SrsStream* stream = tag_stream;
    if ((ret = stream->initialize(data, size)) != ERROR_SUCCESS) {
        return ret;
    }

    // audio decode
    if (!stream->require(1)) {
        ret = ERROR_MP3_DECODE_ERROR;
        srs_error("mp3 decode audio sound_format failed. ret=%d", ret);
        return ret;
    }

    // @see: E.4.2 Audio Tags, video_file_format_spec_v10_1.pdf, page 76
    int8_t sound_format = stream->read_1bytes();

    // @see: SrsAvcAacCodec::audio_aac_demux
    //int8_t sound_type = sound_format & 0x01;
    //int8_t sound_size = (sound_format >> 1) & 0x01;
    //int8_t sound_rate = (sound_format >> 2) & 0x03;
    sound_format = (sound_format >> 4) & 0x0f;

    if ((SrsCodecAudio)sound_format != SrsCodecAudioMP3) {
        ret = ERROR_MP3_DECODE_ERROR;
        srs_error("mp3 required, format=%d. ret=%d", sound_format, ret);
        return ret;
    }

    if (!stream->require(1)) {
        ret = ERROR_MP3_DECODE_ERROR;
        srs_error("mp3 decode aac_packet_type failed. ret=%d", ret);
        return ret;
    }

    return writer->write(data + stream->pos(), size - stream->pos(), NULL);
}

#endif

